18400925 has 6 divisors (see below), whose sum is σ = 22817178. Its totient is φ = 14720720.

The previous prime is 18400909. The next prime is 18400927. The reversal of 18400925 is 52900481.

It can be written as a sum of positive squares in 3 ways, for example, as 1844164 + 16556761 = 1358^2 + 4069^2 .

It is not a de Polignac number, because 18400925 - 2⁴ = 18400909 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18400927) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 367994 + ... + 368043.

It is an arithmetic number, because the mean of its divisors is an integer number (3802863).

Almost surely, 2^18400925 is an apocalyptic number.

It is an amenable number.

18400925 is a deficient number, since it is larger than the sum of its proper divisors (4416253).

18400925 is an equidigital number, since it uses as much as digits as its factorization.

18400925 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 736047 (or 736042 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 29.

The square root of 18400925 is about 4289.6299374188. The cubic root of 18400925 is about 264.0056482186.

The spelling of 18400925 in words is "eighteen million, four hundred thousand, nine hundred twenty-five".